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Date and Time of the Query: 2019-06-17 T22:51:15 PDT
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For refcode 2004ApJ...601..142C:
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2004ApJ...601..142C Stacking Searches for Gamma-Ray Emission above 100 MeV from Radio and Seyfert Galaxies A. N. Cillis, R. C. Hartman, and D. L. Bertsch Abstract. The EGRET telescope on board Compton Gamma Ray Observatory detected more than 60 sources of high-energy gamma radiation associated with active galactic nuclei (AGNs). All but one of those belong to the blazar subclass; the only exception is the nearby radio galaxy Centaurus A. Since there is no obvious reason other than proximity to expect Cen A to be the only nonblazar AGN emitting in high-energy gamma rays, we have utilized the "stacking" technique to search for emission above 100 MeV from two nonblazar AGN subclasses, radio galaxies and Seyfert galaxies. Maps of gamma-ray counts, exposure, and diffuse background have been created, then co-added in varying numbers based on sorts by redshift, 5 GHz flux density, and optical brightness, and finally tested for gamma-ray emission. No detection significance greater than 2 {sigma} has been found for any subclass, sorting parameter, or number of objects co-added. Monte Carlo simulations have also been performed to validate the technique and estimate the significance of the results. Keywords: Galaxies: Active, Galaxies: Seyfert, Gamma Rays: Observations
Retrieve 140 NED objects in this reference.
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